A prominent women’s advocacy group and an organization that campaigns against sex trafficking told The Daily Caller that New Jersey Democrat Bob Menendez should resign from his U.S. Senate seat, if allegations that he slept with underage prostitutes in the Dominican Republic are accurate.

Amy Siskind, president of The New Agenda, told TheDC on Wednesday that “[t]o the extent these allegations are proven true, Sen Bob Menendez should resign from his position immediately.”

In a statement Wednesday evening, Kwame Fosu, a policy director at the Rebecca Project for Human Rights, said his organization agrees that Menendez should step down from the Senate if the allegations against him are true.

Fosu’s organization advocates for victims of sex trafficking and other vulnerable women and girls in the U.S. and Africa. It is best known for organizing a campaign and a congressional hearing that resulted in the online classified-ad website Craigslist discontinuing its lucrative “adult services” section.

Tricia Enright, the press secretary for Sen. Menendez, did not immediately respond to an email seeking a reaction to the two statements.

Menendez has come under fire since TheDC reported on January 25 that a Dominican prostitute said she was paid to have sex with him whn she was 16 years old.

On Tuesday night, the FBI raided the Florida clinic of an eye doctor who has been a longtime donor to Menendez’s campaigns. According to a whistle-blower who published a cache of documents online on Jan. 24, Dr. Salomon Melgen provided prostitutes to Menendez and flew him to a posh Dominican resort on his private jet on several occasions. (RELATED: FBI raids Florida eye clinic of Menendez donor)

A Dominican government official told TheDC in November that Melgen and Menendez regularly held alcohol-fueled sex parties at Melgen’s home on the grounds of the Casa de Campo resort.